Pump

ABSTRACT

A housing of a pump includes a fluid inlet and a fluid outlet. A rotor of the pump is disposed in the housing and includes a rotating portion, a magnet, and a bearing. The magnet is disposed on one side of the rotating portion. The bearing is disposed in the center of the rotating portion. A stator is disposed in the housing and corresponds to the magnet of the rotor, providing electromagnetic force required for rotation of the rotor. The rotating portion, magnet, and bearing are integrally formed as single unit by injection molding.

BACKGROUND

The invention relates to a pump, and in particular to a centrifugal pump with an integrally formed rotor.

Referring to FIG. 1, a conventional centrifugal pump comprises a rotating portion 10, a bearing 12, and a magnet 14. The rotating portion 10, bearing 12, and magnet 14 are individually and separately manufactured and then assembled together by press fitting to form a rotor.

As the rotating portion 10, bearing 12, and magnet 14 respectively provide tolerances, deviation of concentricity and roundness of the rotor after assembly is large. Operation of the centrifugal pump is thus adversely affected. Namely, moment of inertia, vibration, and noise may be generated during operation of the centrifugal pump, adversely affecting output performance thereof.

Moreover, because the rotating portion 10, bearing 12, and magnet 14 are individually and separately manufactured and then assembled together by press fitting, connection and engagement therebetween is weak, reducing reliability of the rotor.

SUMMARY

Accordingly, the present invention provides a pump comprising a housing, a rotor, and a stator. The housing comprises a fluid inlet and a fluid outlet. The rotor is disposed in the housing and comprises a rotating portion, a magnet, and a bearing. The magnet is disposed on one side of the rotating portion. The bearing is disposed in the center of the rotating portion. The stator is disposed in the housing and corresponds to the magnet of the rotor, providing electromagnetic force required for rotation of the rotor. The rotating portion, magnet, and bearing are integrally formed.

The rotor is integrally formed by plastic injection molding.

The magnet is disposed in the interior or exterior of the rotating portion.

The stator is disposed in the interior or exterior of the rotor.

The pump further comprises a shaft axially penetrating the rotor.

The housing further comprises a top cover and a frame body. An accommodation chamber is formed between the top cover and the frame body for accommodating the rotor.

The housing further comprises a bottom cover. A sealed chamber is formed between the bottom cover and the frame body for accommodating the stator.

The stator comprises a plurality of stacked silicon steel sheets and a coil.

The pump comprises a centrifugal pump.

The rotor comprises a plurality of blades on a top surface thereof.

During integral formation of the rotor, the magnet and bearing are placed in a mold forming the rotor. The rotor is integrally formed with the magnet and bearing by plastic injection molding. The housing, rotor, shaft, and stator are then assembled to form the centrifugal pump.

The centrifugal pump can be an outer-rotor type or inner-rotor type pump. In the outer-rotor type pump, the stator is disposed in the interior of the rotor. In the inner-rotor type pump, the stator is disposed in the exterior of the rotor.

DESCRIPTION OF THE DRAWINGS

The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

FIG. 1 is a schematic exploded view of a rotor of a conventional centrifugal pump;

FIG. 2A is a schematic cross section of a rotor of an outer-rotor type centrifugal pump of an embodiment of the invention;

FIG. 2B is a schematic cross section of a rotor of an inner-rotor type centrifugal pump of an embodiment of the invention;

FIG. 3A is a schematic cross section of an outer-rotor type centrifugal pump of an embodiment of the invention; and

FIG. 3B is a schematic cross section of an inner-rotor type centrifugal pump of an embodiment of the invention.

DETAILED DESCRIPTION

First embodiment

Referring to FIG. 2A and FIG. 3A, the (outer-rotor type) centrifugal pump comprises a housing 20, a rotor 22, a stator 24, and a shaft 26. The stator 24 is disposed in the interior of the rotor 22. The shaft 26 axially penetrates the rotor 22.

The rotor 22, stator 24, and shaft 26 are disposed in the housing 20 comprising a top cover 201, a frame body 202, and a bottom cover 203. An accommodation chamber is formed between the top cover 201 and the frame body 202 for accommodating the rotor 22. The top cover 201 comprises a fluid inlet 2011 and a fluid outlet 2012, both shown by dashed lines in FIG. 3A. The fluid inlet 2011 and fluid outlet 2012 respectively take in and output fluid, such as water, when the centrifugal pump operates. The bottom cover 203 is disposed opposite the top cover 201. A sealed chamber is formed between the bottom cover 203 and the frame body 202 for accommodating the stator 24. Two ends of the shaft 26 are fixed to the top cover 201 and frame body 202, respectively. The rotor 22 rotates around the shaft 26.

The rotor 22 comprises a plastic rotating portion 221, a magnet 222, a bearing 223, and a plurality of blades 224. The magnet 222 is disposed on the inner wall of the rotating portion 221. The bearing 223 is disposed in the center of the rotating portion 221 and supports the shaft 26. The blades 224 are formed on the top surface of the rotating portion 221. A gap exists between the rotor 22 and the top cover 201 and between the rotor 22 and the frame body 202, allowing the fluid to flow therethrough.

The stator 24 is disposed in the interior of the rotor 22 and comprises a plurality of stacked silicon steel sheets and a coil surrounding the silicon steel sheets. The stator 24 corresponds to and is coupled to the rotor 22. When the coil is applied with electricity, electromagnetic force is generated to rotate the rotor 22.

The rotor 22 is integrally formed. Specifically, during integral formation of the rotor 22, the magnet 222 and bearing 223 are placed in a mold forming the rotor 22. The rotating portion 221 is integrally formed with the magnet 222 and bearing 223 as a single unit by plastic injection molding. The housing 20, rotor 22, stator 24, and shaft 26 are then assembled to form the centrifugal pump.

Second embodiment

Referring to FIG. 2B and FIG. 3B, the (inner-rotor type) centrifugal pump comprises a housing 30, a rotor 32, a stator 34, and a shaft 36. The stator 34 is disposed in the exterior of the rotor 32. The shaft 36 axially penetrates the rotor 32.

The rotor 32, stator 34, and shaft 36 are disposed in the housing 30 comprising a top cover 301, a frame body 302, and a bottom cover 303. An accommodation chamber is formed between the top cover 301 and the frame body 302 for accommodating the rotor 32. The top cover 301 comprises a fluid inlet 3011 and a fluid outlet 3012, both shown by dashed lines in FIG. 3B. The fluid inlet 3011 and fluid outlet 3012 respectively take in and output fluid, such as water, when the centrifugal pump operates. The bottom cover 303 is disposed opposite the top cover 301. A sealed chamber is formed between the bottom cover 303 and the frame body 302 for accommodating the stator 34. Two ends of the shaft 36 are fixed to the top cover 301 and frame body 302, respectively. The rotor 32 rotates around the shaft 36.

The rotor 32 comprises a plastic rotating portion 321, a magnet 322, a bearing 323, and a plurality of blades 324. The magnet 322 is disposed on the outer wall of the rotating portion 321. The bearing 323 is disposed in the center of the rotating portion 321 and supports the shaft 36. The blades 324 are formed on the top surface of the rotating portion 321. A gap exists between the rotor 32 and the top cover 301 and between the rotor 32 and the frame body 302, allowing the fluid to flow therethrough.

The stator 34 is disposed in the exterior of the rotor 32 and comprises a plurality of stacked silicon steel sheets and a coil surrounding the silicon steel sheets. The stator 34 corresponds to and is coupled to the rotor 32. When the coil is applied with electricity, electromagnetic force is generated to rotate the rotor 32.

Similarly, the rotor 32 is integrally formed. During integral formation of the rotor 32, the magnet 322 and bearing 323 are placed in a mold forming the rotor 32. The rotating portion 321 is integrally formed with the magnet 322 and bearing 323 as a single unit by plastic injection molding. The housing 30, rotor 32, stator 34, and shaft 36 are then assembled to form the centrifugal pump.

In conclusion, in the disclosed centrifugal pumps, the rotors are integrally formed, such that manufacturing costs thereof are reduced. Moreover, because the precision of each member in the rotors is promoted or the tolerance provided by each member therein is reduced after injection molding, concentricity and roundness of the rotors are enhanced. As connection strength and reliability of the disclosed centrifugal pumps are enhanced, moment of inertia, vibration, and noise provided thereby are reduced.

While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. 

1. A pump, comprising: a housing having an inlet and an outlet; a rotor disposed in the housing and comprising a rotating portion, a magnet, and a bearing, wherein the magnet is disposed on one side of the rotating portion, and the bearing is disposed in the center of the rotating portion; and a stator disposed in the housing and corresponding to the magnet of the rotor for providing electromagnetic force required for rotation of the rotor; wherein the rotating portion, magnet, and bearing are integrally formed as a single unit.
 2. The pump as claimed in claim 1, wherein the rotor is integrally formed by plastic injection molding.
 3. The pump as claimed in claim 1, wherein the magnet is disposed in the interior of the rotating portion.
 4. The pump as claimed in claim 3, wherein the stator is disposed in the interior of the rotor.
 5. The pump as claimed in claim 1, wherein the magnet is disposed in the exterior of the rotating portion.
 6. The pump as claimed in claim 5, wherein the stator is disposed in the exterior of the rotor.
 7. The pump as claimed in claim 1, further comprising a shaft axially penetrating the rotor.
 8. The pump as claimed in claim 7, wherein the housing further comprises a top cover and a frame body, and an accommodation chamber is formed between the top cover and the frame body for accommodating the rotor.
 9. The pump as claimed in claim 8, wherein the housing further comprises a bottom cover, and a sealed chamber is formed between the bottom cover and the frame body for accommodating the stator.
 10. The pump as claimed in claim 1, wherein the stator comprises a plurality of stacked silicon steel sheets and a coil.
 11. The pump as claimed in claim 1, wherein the pump is a centrifugal pump.
 12. The pump as claimed in claim 1, wherein the rotor further comprises a plurality of blades on a top surface thereof. 